Anyone understand how Google location actually tracks you

I have looked at the maps for the last few days and the data shown looks wrong.
What does it use as a tracking system, is it the position of mobile base stations?
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Thanks

I wondered about this myself, I stand corrected but I do not think it uses the satellites, I think it check your coordination between the telephone masks

As far as I'm aware, and it seems to correspond in my experience, it uses whatever it can; if you have GPS on it uses that, if you wifi on it can use wifi locations and if not it can uses mobile base station information

It users GPS and phone masts when it can't get a phone signal. The phone signal should be acurate within a few miles and the GPS within a few meters.

Only saw mine go massively wrong once. It had me over 1000 miles off , but I was traveling though the Bermuda triangle at the time.